The Scot says he will only pick youngsters if he feels they are fully ready for the first-team.
Villa currently sit 15 points from safety at the foot of the Premier League with only five games remaining and are all but certain to drop into the second tier of English football for the first time since 1987.
They could already be relegated by the time they face Manchester United on Saturday afternoon if Norwich City avoid defeat at home to fellow strugglers Sunderland in the lunchtime kick-off, leading fans to call for Black to throw the kids into the mix for the rest of their potential dead rubbers fixtures.
The 52-year-old Scot was impressed by the fight the U21s showed in Monday night’s 3-2 win over West Ham United at Villa Park – when tensions boiled over towards the end after centre-back Kevin Toner was sent off for a strong challenge – but he also stressed that his job for the remainder of the campaign is to get results rather than focus on the future.
Speaking at his pre-match press conference ahead of the trip to Old Trafford, Black told reporters: “There was a lot of passion, I must admit. To be fair, whenever I’ve watched the Under-21s there’s always been passion and energy because they’re ambitious and want to get into the first-team, I can understand that.
“However, under the circumstances the other night, they’re kids learning about football, and that can’t really take place on a [Premier League] football field, unfortunately.
“I can understand what the fans are saying, but we have to be professional and we’re preparing people for the professional game. If that happened every Saturday at Aston Villa, it isn’t necessarily what the fans would like.
“I’m not closed off to anything," Black continued "I worked as an academy director at Celtic for a number of years and I know how difficult it is to get players through and how keen you are to give players a chance because you believe in them.
"But what I won't do is put kids in if I don't think they are physically, tactically or mentally ready to play in the first-team under the circumstances that they would have to do in this moment in time against the clubs we’re playing against.
"First and foremost, I want to get a result for Aston Villa. What that result is – whether it’s a 1-0 defeat in which we’ve played exceptionally well or a 0-0 – I’ve still got to focus on that rather than using this as a development programme.
"But if there are people I think are capable of ticking the boxes then I will certainly throw them in."
Among the youngsters who could potentially feature for Black’s side, Under-21 captain Jordan Lyden and 17-year-old winger Andre Green have already made their first-team debuts this season, while striker Keinan Davis, defender-cum-midfielder Niall Mason and the aformentioned Toner have also been around the senior setup in recent months
The likes of Rory Hale, Khalid Abdo and new boy Oscar Borg impressed in Monday night’s victory over the Hammers as well, but it sounds like supporters might have to wait until next season before seeing them in first-team action.